Transfercase swap
 

So this is definitely my first post, but I've been looking for a few hours and can't find anything on this. Maybe wondering if someone has done or tried this.

Being that the H3s are AWD, I was wondering if anyone has tried swapping a transfercase from a canyon/colorado that would have the 2hi option? That way you would get some better MPGs as well as a little less stress on front end components not having power to them all the time?

I just bought a 2007 H3, my first hummer and love it so far!

cant say that i have heard of anybody else attempting it. would def be interested if its possible. only getting 15 mpg city right now. could def use some more mpg's.

I haven't heard anything about anyone doing it either, it would be nice in concept, but I do not think in the end the savings in fuel and wear and tear would out weigh the cost of the swap. unlike a jeep our tcases are controlled by the bcm I believe. In order to do it you would also have to work with programming the computer to not only coincide with your current shift buttons but also your transmission, lockers if equipped, etc. I'm also not sure of the gearing ratio of the Colorado tcase, I think ours have a higher lower range, but don't take my word on this.

You would also need front axle disconnect if using a 2WD transfercase mode. You don't want the front end spinning the driveshaft to the transfercase.

Why would it matter if the front drive shaft spins? There are thousands of vehicles like that. Jeeps being most common I would think.

You do not want the disconnect that GM uses. On the S10 platform we actually sell a AWD shaft that they swap in to get rid of the disconnect as it is a weak point. There is nothing wrong with the drive shaft spinning and there is no noticeable loss in MPG from that.

It would not be just the drive shaft that would continue to spin. Without the ability to unlock the front hubs, the front drive shaft, gears, half shafts and hubs must all be pushed from the rear. In other words, a T case swap by itself is not going to do squat to save MPG or component wear, the entire front drive line is still being spun by the rotating tires.

You would need a 2WD selectable T Case and hubs that can be disengaged, plus all that would have to fit, and be TCCM compatible.

I think the greatest aspect fo the H3 is that it is AWD

AWD plus 4-wheel traction control and stability control!

Full time 4wheel drive is what HUMMERs have. There is a difference between the two.